pgsql: doc PG 17 relnotes: adjust IN wording

doc PG 17 relnotes: adjust IN wording

Reported-by: David Rowley

Discussion: /messages/by-id/CAApHDvqmW0wQRam4paRbHvLQA+w5CJOCno4BCu=NFRLRhYhtRw@mail.gmail.com

Backpatch-through: master

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/8fea1bd5411b793697a4c9087c403887e050c4ac

Modified Files
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doc/src/sgml/release-17.sgml | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)